This paper presents a low power 10 bit 300 ksps successive approximation register analog-to-digital converter （SAR ADC） which is applied in wireless sensor network （WSN） applications. A single ended energy- saving split capacitor DAC array and a latch comparator with a rail to rail input stage are utilized to implement the ADC, which can reduce power dissipation while expanding the full scale input range and improve the signal-to- noise ratio （SNR）. For power optimization the supply voltage of the SAR ADC is designed to be as low as 2 V. Four analog input channels are designed which make the ADC more suitable for WSN applications. The prototype circuit is fabricated using 3.3 V, 0.35μm 2P4M CMOS technology and occupies an active chip area of 1.23 mm2. The test results show that the power dissipation is only 200μW at a 2 V power supply and a sampling rate of 166 ksps. The calculated SNR is 58.25 dB, the ENOB is 9.38 bit and the FOM is 4.95 p J/conversion-step.
Based on the ultra-thin strained silicon-on-insulator（s SOI） technology, by creatively using a hydrofluoric acid（HF）vapor corrosion system to dry etch the Si O2 layer, a large area of suspended strained silicon（s Si） nanomembrane with uniform strain distribution is fabricated. The strain state in the implemented nanomembrane is comprehensively analyzed by using an UV-Raman spectrometer with different laser powers. The results show that the inherent strain is preserved while there are artificial Raman shifts induced by the heat effect, which is proportional to the laser power. The suspended s SOI nanomembrane will be an important material for future novel high-performance devices.
